﻿#region Copyright and Licensing Notice
// Copyright (C) 2011 Steven Bosnick
// 
// This program is open source software; you can redistribute it 
// and/or modifiy it under the terms of the Eclipse Public License,
// version 1.0.
// 
// This program is distributed in the hope that it will be useful, 
// but WITHOUT ANY WARRANTY; without even the implied
// warranty of MERCHANTABILITY or FITNESS FOR A 
// PARTICULAR PURPOSE. See the Eclipse Public License for more
// details.
// 
// You should have received a copy of the Eclipse Public License 
// along with this program; if not, you can find a copy at
// "http://www.opensource.org/licenses/eclipse-1.0.php".
#endregion
using System;
using BitwiseOre.SharedMemory.Core.Common;

namespace BitwiseOre.SharedMemory.Core.Primatives
{
    internal sealed class WriteBuffer : IWriteBuffer
    {
        private readonly IBufferLayout _layout;

        public WriteBuffer(IBufferLayout layout)
        {
            _layout = layout;
            _layout.Length = 0;
        }

        public bool WriteByte(byte value)
        {
            if (IsPastEnd)
            {
                _layout.Contents[_layout.Length++] = value;
                return true;
            }
            return false;
        }

        public int WriteArraySegment(ArraySegment<byte> array)
        {
            if (IsPastEnd)
            {
                var count = _layout.Contents.WriteArraySegment(_layout.Length, array);
                _layout.Length += count;
                return count;
            }
            return 0;
        }

        public bool IsEmpty
        {
            get { return _layout.Length == 0; }
        }

        private bool IsPastEnd
        {
            get { return _layout.Length < _layout.Contents.Capacity; }
        }

        public override string ToString()
        {
            return string.Format("Length: {0}", _layout.Length);
        }
    }
}